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Bastawrous M, Ghosh Biswas R, Soong R, Jouda M, MacKinnon N, Mager D, Korvink JG, Simpson AJ. Lenz Lenses in a Cryoprobe: Boosting NMR Sensitivity Toward Environmental Monitoring of Mass-Limited Samples. Anal Chem 2023; 95:1327-1334. [PMID: 36576271 DOI: 10.1021/acs.analchem.2c04203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Nuclear magnetic resonance (NMR) spectroscopy is commonly employed in a wide range of metabolomic research. Unfortunately, due to its relatively low sensitivity, smaller samples become challenging to study by NMR. Cryoprobes can be used to increase sensitivity by cooling the coil and preamplifier, offering sensitivity improvements of ∼3 to 4x. Alternatively, microcoils can be used to increase mass sensitivity by improving sample filling and proximity, along with decreased electrical resistance. Unfortunately, combining the two approaches is not just technically challenging, but as the coil decreases, so does its thermal fingerprint, reducing the advantage of cryogenic cooling. Here, an alternative solution is proposed in the form of a Lenz lens inside a cryoprobe. Rather than replacing the detection coil, Lenz lenses allow the B1 field from a larger coil to be refocused onto a much smaller sample area. In turn, the stronger B1 field at the sample provides strong coupling to the cryocoil, improving the signal. By combining a 530 I.D. Lenz lens with a cryoprobe, sensitivity was further improved by 2.8x and 3.5x for 1H and 13C, respectively, over the cryoprobe alone for small samples. Additionally, the broadband nature of the Lenz lenses allowed multiple nuclei to be studied and heteronuclear two-dimensional (2D) NMR approaches to be employed. The sensitivity improvements and 2D capabilities are demonstrated on 430 nL of hemolymph and eight eggs (∼350 μm O.D.) from the model organismDaphnia magna. In summary, combining Lenz lenses with cryoprobes offers a relatively simple approach to boost sensitivity for tiny samples while retaining cryoprobe advantages.
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Affiliation(s)
- Monica Bastawrous
- Environmental NMR Center, University of Toronto, 1265 Military Trail, Toronto, Ontario M1C 1A4, Canada
| | - Rajshree Ghosh Biswas
- Environmental NMR Center, University of Toronto, 1265 Military Trail, Toronto, Ontario M1C 1A4, Canada
| | - Ronald Soong
- Environmental NMR Center, University of Toronto, 1265 Military Trail, Toronto, Ontario M1C 1A4, Canada
| | - Mazin Jouda
- Institute of Microstructure Technology, Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen, Germany
| | - Neil MacKinnon
- Institute of Microstructure Technology, Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen, Germany
| | - Dario Mager
- Institute of Microstructure Technology, Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen, Germany
| | - Jan G Korvink
- Institute of Microstructure Technology, Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen, Germany
| | - Andre J Simpson
- Environmental NMR Center, University of Toronto, 1265 Military Trail, Toronto, Ontario M1C 1A4, Canada
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Qi H, Cao H, Zhao Y, Cao Y, Jin Q, Wang Y, Zhang K, Deng D. Cloning and functional analysis of the molting gene CYP302A1 of Daphnia sinensis. Front Zool 2023; 20:2. [PMID: 36635746 PMCID: PMC9835317 DOI: 10.1186/s12983-023-00483-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2022] [Accepted: 01/07/2023] [Indexed: 01/14/2023] Open
Abstract
BACKGROUND Molting is an important physiological process in the growth and development of arthropoda, which is mainly regulated by juvenile hormone and ecdysone. CYP302A1 is a key enzyme which plays a critical role in the synthesis of ecdysone in insects, but it has not been identified in cladocera. RESULTS The CYP302Al gene of Daphnia sinensis was cloned and its function was analyzed in this paper. The CYP302Al gene of D. sinensis was 5926 bp in full-length, with an open reading frame (ORF) of 1596 bp that encoded 531 amino acids (aa), a molecular weight of 60.82 kDa and an isoelectric point of 9.29. The amino acid sequence analysis revealed that there were five characteristic conserved regions of cytochrome P450 family (namely helix-C, helix-K, helix-I, PERF and heme-binding). In dsRNA mediated experiment, the expression level of CYP302A1 gene decreased significantly (knock-down of 56.22%) in the 5% Escherichia coli concentration treatment. In addition, the expression levels of EcR and USP and HR3 genes in the downstream were also significantly decreased, whereas that of FTZ-f1 gene increased significantly. In the 5% E. coli treatment, the molting time at maturity of D. sinensis prolonged, and the development of embryos in the incubation capsule appeared abnormal or disintegrated. The whole-mount in situ hybridization showed that the CYP302A1 gene of D. sinensis had six expression sites before RNA interference (RNAi), which located in the first antennal ganglion, ovary, cecae, olfactory hair, thoracic limb and tail spine. However, the expression signal of the CYP302A1 gene of D. sinensis disappeared in the first antennal ganglion and obviously attenuated in the ovary after RNAi. CONCLUSION The CYP302A1 gene played an important role in the ecdysone synthesis pathway of D. sinensis, and the knock-down of the gene affected the molting and reproduction of D. sinensis.
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Affiliation(s)
- Huiying Qi
- grid.440755.70000 0004 1793 4061School of Life Science, Huaibei Normal University, Huaibei, 235000 People’s Republic of China
| | - Huijuan Cao
- grid.440755.70000 0004 1793 4061School of Life Science, Huaibei Normal University, Huaibei, 235000 People’s Republic of China
| | - Yajie Zhao
- grid.440755.70000 0004 1793 4061School of Life Science, Huaibei Normal University, Huaibei, 235000 People’s Republic of China
| | - Yaqin Cao
- grid.440755.70000 0004 1793 4061School of Life Science, Huaibei Normal University, Huaibei, 235000 People’s Republic of China
| | - Qide Jin
- grid.440755.70000 0004 1793 4061School of Life Science, Huaibei Normal University, Huaibei, 235000 People’s Republic of China
| | - Yeping Wang
- grid.440755.70000 0004 1793 4061School of Life Science, Huaibei Normal University, Huaibei, 235000 People’s Republic of China
| | - Kun Zhang
- grid.440755.70000 0004 1793 4061School of Life Science, Huaibei Normal University, Huaibei, 235000 People’s Republic of China
| | - Daogui Deng
- grid.440755.70000 0004 1793 4061School of Life Science, Huaibei Normal University, Huaibei, 235000 People’s Republic of China
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Hamza W, Hazzouri KM, Sudalaimuthuasari N, Amiri KMA, Neretina AN, Al Neyadi SES, Kotov AA. Genome Assembly of a Relict Arabian Species of Daphnia O. F. Müller (Crustacea: Cladocera) Adapted to the Desert Life. Int J Mol Sci 2023; 24:ijms24010889. [PMID: 36614331 PMCID: PMC9820869 DOI: 10.3390/ijms24010889] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 12/29/2022] [Accepted: 01/02/2023] [Indexed: 01/05/2023] Open
Abstract
The water flea Daphnia O.F. Müller 1776 (Crustacea: Cladocera) is an important model of recent evolutionary biology. Here, we report a complete genome of Daphnia (Ctenodaphnia) arabica (Crustacea: Cladocera), recently described species endemic to deserts of the United Arab Emirates. In this study, genome analysis of D. arabica was carried out to investigate its genomic differences, complexity as well as its historical origins within the subgenus Daphnia (Ctenodaphnia). Hybrid genome assembly of D. arabica resulted in ~116 Mb of the assembled genome, with an N50 of ~1.13 Mb (BUSCO score of 99.2%). From the assembled genome, in total protein coding, 5374 tRNA and 643 rRNA genes were annotated. We found that the D. arabica complete genome differed from those of other Daphnia species deposited in the NCBI database but was close to that of D. cf. similoides. However, its divergence time estimate sets D. arabica in the Mesozoic, and our demographic analysis showed a great reduction in its genetic diversity compared to other Daphnia species. Interestingly, the population expansion in its diversity occurred during the megadrought climate around 100 Ka ago, reflecting the adaptive feature of the species to arid and drought-affected environments. Moreover, the PFAM comparative analysis highlights the presence of the important domain SOSS complex subunit C in D. arabica, which is missing in all other studied species of Daphnia. This complex consists of a few subunits (A, B, C) working together to maintain the genome stability (i.e., promoting the reparation of DNA under stress). We propose that this domain could play a role in maintaining the fitness and survival of this species in the desert environment. The present study will pave the way for future research to identify the genes that were gained or lost in this species and identify which of these were key factors to its adaptation to the harsh desert environment.
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Affiliation(s)
- Waleed Hamza
- Biology Department, College of Science, United Arab Emirates University, Al Ain P.O. Box 15551, United Arab Emirates
- Correspondence: (W.H.); (A.A.K.)
| | - Khaled M. Hazzouri
- Khalifa Center for Genetic Engineering and Biotechnology, United Arab Emirates University, Al Ain P.O. Box 15551, United Arab Emirates
| | - Naganeeswaran Sudalaimuthuasari
- Khalifa Center for Genetic Engineering and Biotechnology, United Arab Emirates University, Al Ain P.O. Box 15551, United Arab Emirates
| | - Khaled M. A. Amiri
- Biology Department, College of Science, United Arab Emirates University, Al Ain P.O. Box 15551, United Arab Emirates
- Khalifa Center for Genetic Engineering and Biotechnology, United Arab Emirates University, Al Ain P.O. Box 15551, United Arab Emirates
| | - Anna N. Neretina
- A.N. Severtsov Institute of Ecology and Evolution, Russian Academy of Sciences, 119071 Moscow, Russia
| | - Shamma E. S. Al Neyadi
- Biology Department, College of Science, United Arab Emirates University, Al Ain P.O. Box 15551, United Arab Emirates
| | - Alexey A. Kotov
- A.N. Severtsov Institute of Ecology and Evolution, Russian Academy of Sciences, 119071 Moscow, Russia
- Correspondence: (W.H.); (A.A.K.)
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Ebert D. Daphnia as a versatile model system in ecology and evolution. EvoDevo 2022; 13:16. [PMID: 35941607 PMCID: PMC9360664 DOI: 10.1186/s13227-022-00199-0] [Citation(s) in RCA: 30] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Accepted: 06/20/2022] [Indexed: 11/10/2022] Open
Abstract
Water fleas of the genus Daphnia have been a model system for hundreds of years and is among the best studied ecological model organisms to date. Daphnia are planktonic crustaceans with a cyclic parthenogenetic life-cycle. They have a nearly worldwide distribution, inhabiting standing fresh- and brackish water bodies, from small temporary pools to large lakes. Their predominantly asexual reproduction allows for the study of phenotypes excluding genetic variation, enabling us to separate genetic from non-genetic effects. Daphnia are often used in studies related to ecotoxicology, predator-induced defence, host–parasite interactions, phenotypic plasticity and, increasingly, in evolutionary genomics. The most commonly studied species are Daphnia magna and D. pulex, for which a rapidly increasing number of genetic and genomic tools are available. Here, I review current research topics, where the Daphnia model system plays a critical role.
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Affiliation(s)
- Dieter Ebert
- Department of Environmental Sciences, Zoology, University of Basel, Vesalgasse 1, CH-4051, Basel, Switzerland.
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5
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Byeon E, Kim MS, Kim DH, Lee Y, Jeong H, Lee JS, Hong SA, Park JC, Kang HM, Sayed AEDH, Kato Y, Bae S, Watanabe H, Lee YH, Lee JS. The freshwater water flea Daphnia magna NIES strain genome as a resource for CRISPR/Cas9 gene targeting: The glutathione S-transferase omega 2 gene. AQUATIC TOXICOLOGY 2022; 242:106021. [PMID: 34856461 DOI: 10.1016/j.aquatox.2021.106021] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 10/26/2021] [Accepted: 11/07/2021] [Indexed: 02/07/2023]
Abstract
The water flea Daphnia magna is a small freshwater planktonic animal in the Cladocera. In this study, we assembled the genome of the D. magna NIES strain, which is widely used for gene targeting but has no reported genome. We used the long-read sequenced data of the Oxford nanopore sequencing tool for assembly. Using 3,231 genetic markers, the draft genome of the D. magna NIES strain was built into ten linkage groups (LGs) with 483 unanchored contigs, comprising a genome size of 173.47 Mb. The N50 value of the genome was 12.54 Mb and the benchmarking universal single-copy ortholog value was 98.8%. Repeat elements in the D. magna NIES genome were 40.8%, which was larger than other Daphnia spp. In the D. magna NIES genome, 15,684 genes were functionally annotated. To assess the genome of the D. magna NIES strain for CRISPR/Cas9 gene targeting, we selected glutathione S-transferase omega 2 (GST-O2), which is an important gene for the biotransformation of arsenic in aquatic organisms, and targeted it with an efficient make-up (25.0%) of mutant lines. In addition, we measured reactive oxygen species and antioxidant enzymatic activity between wild type and a mutant of the GST-O2 targeted D. magna NIES strain in response to arsenic. In this study, we present the genome of the D. magna NIES strain using GST-O2 as an example of gene targeting, which will contribute to the construction of deletion mutants by CRISPR/Cas9 technology.
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Affiliation(s)
- Eunjin Byeon
- Department of Biological Sciences, College of Science, Sungkyunkwan University, Suwon 16419, South Korea
| | - Min-Sub Kim
- Department of Biological Sciences, College of Science, Sungkyunkwan University, Suwon 16419, South Korea
| | - Duck-Hyun Kim
- Department of Biological Sciences, College of Science, Sungkyunkwan University, Suwon 16419, South Korea
| | - Yoseop Lee
- Department of Biological Sciences, College of Science, Sungkyunkwan University, Suwon 16419, South Korea
| | - Haksoo Jeong
- Department of Biological Sciences, College of Science, Sungkyunkwan University, Suwon 16419, South Korea
| | - Jin-Sol Lee
- Department of Biological Sciences, College of Science, Sungkyunkwan University, Suwon 16419, South Korea
| | - Sung-Ah Hong
- Department of Chemistry, College of Nature Sciences, Hanyang University, Seoul 04763, South Korea
| | - Jun Chul Park
- Département des Sciences, Université Sainte-Anne, Church Point, NS B0W 1M0, Canada
| | - Hye-Min Kang
- Marine Biotechnology Research Center, Korea Institute of Ocean Science and Technology, Busan 49111, South Korea
| | - Alaa El-Din H Sayed
- Department of Zoology, Faculty of Sciences, Assiut University, Assiut 71516, Egypt
| | - Yasuhiko Kato
- Department of Biotechnology, Graduate School of Engineering, Osaka University, Osaka 565-0871, Japan
| | - Sangsu Bae
- Department of Chemistry, College of Nature Sciences, Hanyang University, Seoul 04763, South Korea
| | - Hajime Watanabe
- Department of Biotechnology, Graduate School of Engineering, Osaka University, Osaka 565-0871, Japan
| | - Young Hwan Lee
- Department of Biological Sciences, College of Science, Sungkyunkwan University, Suwon 16419, South Korea.
| | - Jae-Seong Lee
- Department of Biological Sciences, College of Science, Sungkyunkwan University, Suwon 16419, South Korea.
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6
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Cornetti L, Fields PD, Ebert D. Genomic characterization of selfing in the cyclic parthenogen Daphnia magna. J Evol Biol 2021; 34:792-802. [PMID: 33704857 DOI: 10.1111/jeb.13780] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2020] [Revised: 02/23/2021] [Accepted: 03/06/2021] [Indexed: 11/29/2022]
Abstract
Inbreeding refers to the fusion of related individuals' gametes, with self-fertilization (selfing) being an extreme form of inbreeding-involving gametes produced by the same individual. Selfing is expected to reduce heterozygosity by an average of 50% in one generation; however, little is known about the empirical variation on a genome level surrounding this figure and the factors that affect variation. We selfed genotypes of the cyclic parthenogen Daphnia magna and analysed whole genomes of mothers and selfed offspring, observing the predicted 50% heterozygosity reduction on average. We also saw substantial variation around this value and significant differences among mother-offspring pairs. Crossover analysis confirmed the known trend of recombination occurring more often towards the telomeres. This effect was shown, through simulations, to increase the variance of heterozygosity reduction compared to when a uniform distribution of crossovers was used. Similarly, we simulated inbred line production after several generations of selfing and we observed higher variance in achieved homozygosity when we consider a higher recombination rate towards the telomeres. Our empirical and simulation study highlights that the expected mean values of heterozygosity reduction show remarkable variation, which can help understand, for example, differences among inbred individuals.
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Affiliation(s)
- Luca Cornetti
- Department of Environmental Sciences, Zoology, University of Basel, Basel, Switzerland
| | - Peter D Fields
- Department of Environmental Sciences, Zoology, University of Basel, Basel, Switzerland
| | - Dieter Ebert
- Department of Environmental Sciences, Zoology, University of Basel, Basel, Switzerland
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7
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Tesson SVM, Sha Y. Population connectivity, dispersal, and swimming behavior in Daphnia. Ecol Evol 2021; 11:2873-2885. [PMID: 33767843 PMCID: PMC7981204 DOI: 10.1002/ece3.7246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 12/30/2020] [Accepted: 01/12/2021] [Indexed: 11/23/2022] Open
Abstract
The water flea Daphnia has the capacity to respond rapidly to environmental stressors, to disperse over large geographical scales, and to preserve its genetic material by forming egg banks in the sediment. Spatial and temporal distributions of D. magna have been extensively studied over the last decades using behavioral or genetic tools, although the correlation between the two has rarely been the focus. In the present study, we therefore investigated the population genetic structure and behavioral response to a lethal threat, ultraviolet radiation (UVR), among individuals from two different water bodies. Our results show two genetic populations with moderate gene flow, highly correlated with geographical location and with inheritable traits through generations. However, despite the strong genetic differences between populations, we show homogeneous refuge demand between populations when exposed to the lethal threat solar UVR.
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Affiliation(s)
- Sylvie V. M. Tesson
- Department of BiologyAarhus UniversityAarhusDenmark
- Department of BiologyLund UniversityLundSweden
| | - Yongcui Sha
- Department of BiologyLund UniversityLundSweden
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8
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Knigge T, LeBlanc GA, Ford AT. A Crab Is Not a Fish: Unique Aspects of the Crustacean Endocrine System and Considerations for Endocrine Toxicology. Front Endocrinol (Lausanne) 2021; 12:587608. [PMID: 33737907 PMCID: PMC7961072 DOI: 10.3389/fendo.2021.587608] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2020] [Accepted: 01/25/2021] [Indexed: 12/13/2022] Open
Abstract
Crustaceans-and arthropods in general-exhibit many unique aspects to their physiology. These include the requirement to moult (ecdysis) in order to grow and reproduce, the ability to change color, and multiple strategies for sexual differentiation. Accordingly, the endocrine regulation of these processes involves hormones, receptors, and enzymes that differ from those utilized by vertebrates and other non-arthropod invertebrates. As a result, environmental chemicals known to disrupt endocrine processes in vertebrates are often not endocrine disruptors in crustaceans; while, chemicals that disrupt endocrine processes in crustaceans are often not endocrine disruptors in vertebrates. In this review, we present an overview of the evolution of the endocrine system of crustaceans, highlight endocrine endpoints known to be a target of disruption by chemicals, and identify other components of endocrine signaling that may prove to be targets of disruption. This review highlights that crustaceans need to be evaluated for endocrine disruption with consideration of their unique endocrine system and not with consideration of the endocrine system of vertebrates.
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Affiliation(s)
- Thomas Knigge
- Normandy University, FR CNRS 3730 SCALE, UMR-I 02 INERIS-URCA-ULH Environmental Stress and Aquatic Biomonitoring (SEBIO), Université Le Havre Normandie, Le Havre, France
- *Correspondence: Thomas Knigge,
| | - Gerald A. LeBlanc
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, United States
| | - Alex T. Ford
- School of Biological Sciences, Institute of Marine Sciences, University of Portsmouth, Portsmouth, United Kingdom
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9
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Kowal K, Tkaczyk A, Pierzchała M, Bownik A, Ślaska B. Identification of Mitochondrial DNA (NUMTs) in the Nuclear Genome of Daphnia magna. Int J Mol Sci 2020; 21:E8725. [PMID: 33218217 PMCID: PMC7699184 DOI: 10.3390/ijms21228725] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Revised: 11/06/2020] [Accepted: 11/16/2020] [Indexed: 01/30/2023] Open
Abstract
This is the first study in which the Daphnia magna (D. magna) nuclear genome (nDNA) obtained from the GenBank database was analyzed for pseudogene sequences of mitochondrial origin. To date, there is no information about pseudogenes localized in D. magna genome. This study aimed to identify NUMTs, their length, homology, and location for potential use in evolutionary studies and to check whether their occurrence causes co-amplification during mitochondrial genome (mtDNA) analyses. Bioinformatic analysis showed 1909 fragments of the mtDNA of D. magna, of which 1630 were located in ten linkage groups (LG) of the nDNA. The best-matched NUMTs covering >90% of the gene sequence have been identified for two mt-tRNA genes, and they may be functional nuclear RNA molecules. Isolating the total DNA in mtDNA studies, co-amplification of nDNA fragments is unlikely in the case of amplification of the whole tRNA genes as well as fragments of other genes. It was observed that TRNA-MET fragments had the highest level of sequence homology, thus they could be evolutionarily the youngest. The lowest homology was found in the D-loop-derived pseudogene. It may probably be the oldest NUMT incorporated into the nDNA; however, further analysis is necessary.
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Affiliation(s)
- Krzysztof Kowal
- Faculty of Animal Sciences and Bioeconomy, Institute of Biological Bases of Animal Production, University of Life Sciences in Lublin, Akademicka 13 Str., 20-950 Lublin, Poland; (K.K.); (A.T.)
| | - Angelika Tkaczyk
- Faculty of Animal Sciences and Bioeconomy, Institute of Biological Bases of Animal Production, University of Life Sciences in Lublin, Akademicka 13 Str., 20-950 Lublin, Poland; (K.K.); (A.T.)
| | - Mariusz Pierzchała
- Department of Genomics and Biodiversity, Institute of Genetics and Animal Biotechnology of the Polish Academy of Sciences, Postępu 36a Str., 05-552 Jastrzębiec, Poland;
| | - Adam Bownik
- Faculty of Environmental Biology, Department of Hydrobiology and Protection of Ecosystems, University of Life Sciences in Lublin, Dobrzańskiego 37 Str., 20-262 Lublin, Poland;
| | - Brygida Ślaska
- Faculty of Animal Sciences and Bioeconomy, Institute of Biological Bases of Animal Production, University of Life Sciences in Lublin, Akademicka 13 Str., 20-950 Lublin, Poland; (K.K.); (A.T.)
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10
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Inverse or direct detect experiments and probes: Which are “best” for in-vivo NMR research of 13C enriched organisms? Anal Chim Acta 2020; 1138:168-180. [DOI: 10.1016/j.aca.2020.09.065] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Revised: 09/11/2020] [Accepted: 09/30/2020] [Indexed: 01/09/2023]
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11
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An alternative route of bacterial infection associated with a novel resistance locus in the Daphnia-Pasteuria host-parasite system. Heredity (Edinb) 2020; 125:173-183. [PMID: 32561843 PMCID: PMC7490384 DOI: 10.1038/s41437-020-0332-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Revised: 06/07/2020] [Accepted: 06/07/2020] [Indexed: 11/23/2022] Open
Abstract
To understand the mechanisms of antagonistic coevolution, it is crucial to identify the genetics of parasite resistance. In the Daphnia magna–Pasteuria ramosa host–parasite system, the most important step of the infection process is the one in which P. ramosa spores attach to the host’s foregut. A matching-allele model (MAM) describes the host–parasite genetic interactions underlying attachment success. Here we describe a new P. ramosa genotype, P15, which, unlike previously studied genotypes, attaches to the host’s hindgut, not to its foregut. Host resistance to P15 attachment shows great diversity across natural populations. In contrast to P. ramosa genotypes that use foregut attachment, P15 shows some quantitative variation in attachment success and does not always lead to successful infections, suggesting that hindgut attachment represents a less-efficient infection mechanism than foregut attachment. Using a Quantitative Trait Locus (QTL) approach, we detect two significant QTLs in the host genome: one that co-localizes with the previously described D. magna PR locus of resistance to foregut attachment, and a second, major QTL located in an unlinked genomic region. We find no evidence of epistasis. Fine mapping reveals a genomic region, the D locus, of ~13 kb. The discovery of a second P. ramosa attachment site and of a novel host-resistance locus increases the complexity of this system, with implications for both for the coevolutionary dynamics (e.g., Red Queen and the role of recombination), and for the evolution and epidemiology of the infection process.
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12
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Czypionka T, Fields PD, Routtu J, van den Berg E, Ebert D, De Meester L. The genetic architecture underlying diapause termination in a planktonic crustacean. Mol Ecol 2019; 28:998-1008. [PMID: 30592346 DOI: 10.1111/mec.15001] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Revised: 11/15/2018] [Accepted: 11/27/2018] [Indexed: 01/17/2023]
Abstract
Diapause is a feature of the life cycle of many invertebrates by which unfavourable environmental conditions can be outlived. The seasonal timing of diapause allows organisms to adapt to seasonal changes in habitat suitability and thus is key to their fitness. In the planktonic crustacean Daphnia, various cues can induce the production of diapause stages that are resistant to heat, drought or freezing and contain one to two embryos in developmental arrest. Daphnia is a keystone species of many freshwater ecosystems, where it acts as the main link between phytoplankton and higher trophic levels. The correct seasonal timing of diapause termination is essential to maintain trophic interactions and is achieved via a genetically based interpretation of environmental cues like photoperiod and temperature. Field monitoring and modelling studies raised concerns on whether populations can advance their seasonal release from diapause to advances in spring phenology under global change, or if a failure to adapt will cause trophic mismatches negatively affecting ecosystem functioning. Our capacity to understand and predict the evolution of diapause timing requires information about the genetic architecture underlying this trait. In this study, we identified eight quantitative trait loci (QTLs) and four epistatic interactions that together explained 66.5% of the variation in diapause termination in Daphnia magna using QTL mapping. Our results suggest that the most significant QTL is modulating diapause termination dependent on photoperiod and is involved in three of the four detected epistatic interactions. Candidate genes at this QTL could be identified through the integration with genome data and included the presynaptic active zone protein bruchpilot. Our findings contribute to understanding the genomic control of seasonal diapause timing in an ecological relevant species.
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Affiliation(s)
- Till Czypionka
- Laboratory of Aquatic Ecology and Evolutionary Biology, KU Leuven, Leuven, Belgium
| | - Peter D Fields
- Department of Environmental Sciences, Zoology, University of Basel, Basel, Switzerland
| | - Jarkko Routtu
- Department of Environmental Sciences, Zoology, University of Basel, Basel, Switzerland.,Molecular Ecology, Martin-Luther-Universität, Halle-Wittenberg, Germany
| | - Edwin van den Berg
- Laboratory of Aquatic Ecology and Evolutionary Biology, KU Leuven, Leuven, Belgium
| | - Dieter Ebert
- Department of Environmental Sciences, Zoology, University of Basel, Basel, Switzerland
| | - Luc De Meester
- Laboratory of Aquatic Ecology and Evolutionary Biology, KU Leuven, Leuven, Belgium
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13
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Hall MD, Routtu J, Ebert D. Dissecting the genetic architecture of a stepwise infection process. Mol Ecol 2019; 28:3942-3957. [PMID: 31283079 DOI: 10.1111/mec.15166] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Revised: 06/27/2019] [Accepted: 06/28/2019] [Indexed: 02/06/2023]
Abstract
How a host fights infection depends on an ordered sequence of steps, beginning with attempts to prevent a pathogen from establishing an infection, through to steps that mitigate a pathogen's control of host resources or minimize the damage caused during infection. Yet empirically characterizing the genetic basis of these steps remains challenging. Although each step is likely to have a unique genetic and environmental signature, and may therefore respond to selection in different ways, events that occur earlier in the infection process can mask or overwhelm the contributions of subsequent steps. In this study, we dissect the genetic architecture of a stepwise infection process using a quantitative trait locus (QTL) mapping approach. We control for variation at the first line of defence against a bacterial pathogen and expose downstream genetic variability related to the host's ability to mitigate the damage pathogens cause. In our model, the water-flea Daphnia magna, we found a single major effect QTL, explaining 64% of the variance, that is linked to the host's ability to completely block pathogen entry by preventing their attachment to the host oesophagus; this is consistent with the detection of this locus in previous studies. In susceptible hosts allowing attachment, however, a further 23 QTLs, explaining between 5% and 16% of the variance, were mapped to traits related to the expression of disease. The general lack of pleiotropy and epistasis for traits related to the different stages of the infection process, together with the wide distribution of QTLs across the genome, highlights the modular nature of a host's defence portfolio, and the potential for each different step to evolve independently. We discuss how isolating the genetic basis of individual steps can help to resolve discussion over the genetic architecture of host resistance.
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Affiliation(s)
- Matthew D Hall
- Department of Environmental Sciences, Zoology, University of Basel, Basel, Switzerland.,School of Biological Sciences, Monash University, Melbourne, Victoria, Australia
| | - Jarkko Routtu
- Department of Environmental Sciences, Zoology, University of Basel, Basel, Switzerland.,Molecular Ecology, Martin-Luther-Universität, Halle-Wittenberg, Germany
| | - Dieter Ebert
- Department of Environmental Sciences, Zoology, University of Basel, Basel, Switzerland
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14
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Lee BY, Choi BS, Kim MS, Park JC, Jeong CB, Han J, Lee JS. The genome of the freshwater water flea Daphnia magna: A potential use for freshwater molecular ecotoxicology. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2019; 210:69-84. [PMID: 30826642 DOI: 10.1016/j.aquatox.2019.02.009] [Citation(s) in RCA: 77] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Revised: 02/14/2019] [Accepted: 02/14/2019] [Indexed: 06/09/2023]
Abstract
The water flea Daphnia magna is a small planktonic cladoceran. D. magna has been used as a model species for ecotoxicology, as it is sensitive to environmental stressors and environmental changes. Since Daphnia is affected by culture environment and each population/strain has its own ecological and genetic characteristics, its population/strain-based genome information is useful for environmental genomic studies. In this study, we assembled and characterized the genome of D. magna. Using a high-density genetic map of D. magna xinb3, the draft genome was integrated to 10 linkage groups (LGs). The total length of the integrated genome was about 123 Mb with N50 = 10.1 Mb, and the number of scaffolds was 4193 including 10 LGs. A total of 15,721 genes were annotated after manual curation. Orthologous genes were characterized in the genome and compared with other genomes of Daphnia. In addition, we identified defense related genes such as cytochrome P450 (CYP) genes, glutathione S-transferase (GST) genes, and ATP-binding cassette (ABC) genes from the assembled D. magna genome for its potential use in molecular ecotoxicological studies in the freshwater environment. This genomic resource will be helpful to study for a better understanding on molecular mechanism in response to various pollutants.
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Affiliation(s)
- Bo-Young Lee
- Department of Biological Science, College of Science, Sungkyunkwan University, Suwon 16419, South Korea
| | | | - Min-Sub Kim
- Department of Biological Science, College of Science, Sungkyunkwan University, Suwon 16419, South Korea
| | - Jun Chul Park
- Department of Biological Science, College of Science, Sungkyunkwan University, Suwon 16419, South Korea
| | - Chang-Bum Jeong
- Department of Biological Science, College of Science, Sungkyunkwan University, Suwon 16419, South Korea
| | - Jeonghoon Han
- Department of Biological Science, College of Science, Sungkyunkwan University, Suwon 16419, South Korea
| | - Jae-Seong Lee
- Department of Biological Science, College of Science, Sungkyunkwan University, Suwon 16419, South Korea.
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15
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Sison-Mangus MP, Metzger CMJA, Ebert D. Host genotype-specific microbiota do not influence the susceptibility of D. magna to a bacterial pathogen. Sci Rep 2018; 8:9407. [PMID: 29925845 PMCID: PMC6010447 DOI: 10.1038/s41598-018-27681-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Accepted: 06/05/2018] [Indexed: 01/09/2023] Open
Abstract
Host-associated microbiota have been claimed to play a role in hosts' responses to parasitic infections, often protecting the hosts from infection. We tested for such a role in the crustacean Daphnia and the parasitic bacterium Pasteuria ramosa, a widely used model system for host-parasite interactions. We first determined the infection phenotype (i.e., resistotype) of eight clonal D. magna genotypes against four strains of P. ramosa by attachment test, followed by 16 S rDNA amplicon sequencing to determine if their genotype or their parasite resistotype influences the composition of their microbiome. We then reciprocally transplanted the microbiota of two host genotypes with opposite resistotypes to four P. ramosa isolates, followed by a reassessment of their resistotype after transplantation. We found significant differences in microbiome composition and structure between Daphnia genotypes and between Daphnia resistotypes to specific P. ramosa strains. Reciprocal microbiota exchange or making the Daphnia hosts bacteria-free, however, did not influence the resistotypes of the hosts. Thus, in contrary to what has been observed in some taxa, our results suggest that D. magna susceptibility to P. ramosa is strongly dictated by the genetic differences of the hosts and is still dependent on Daphnia's first line of immune defense against the esophageal attachment of P. ramosa, which appears to be uninfluenced by the host's microbiota.
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Affiliation(s)
- Marilou P Sison-Mangus
- Department of Ocean Sciences, University of California Santa Cruz, 1156 High Street, Santa Cruz, CA, 95064, USA.
- Department of Environmental Sciences, Zoology, University of Basel, Vesalgasse 1, 4051, Basel, Switzerland.
| | - César M J A Metzger
- Department of Environmental Sciences, Zoology, University of Basel, Vesalgasse 1, 4051, Basel, Switzerland
- Spiez Laboratory, Austrasse, 3700, Spiez, Switzerland
| | - Dieter Ebert
- Department of Environmental Sciences, Zoology, University of Basel, Vesalgasse 1, 4051, Basel, Switzerland
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16
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Brans KI, Jansen M, Vanoverbeke J, Tüzün N, Stoks R, De Meester L. The heat is on: Genetic adaptation to urbanization mediated by thermal tolerance and body size. GLOBAL CHANGE BIOLOGY 2017; 23:5218-5227. [PMID: 28614592 DOI: 10.1111/gcb.13784] [Citation(s) in RCA: 100] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Accepted: 05/17/2017] [Indexed: 06/07/2023]
Abstract
Worldwide, urbanization leads to tremendous anthropogenic environmental alterations, causing strong selection pressures on populations of animals and plants. Although a key feature of urban areas is their higher temperature ("urban heat islands"), adaptive thermal evolution in organisms inhabiting urban areas has rarely been studied. We tested for evolution of a higher heat tolerance (CTMAX ) in urban populations of the water flea Daphnia magna, a keystone grazer in freshwater ecosystems, by carrying out a common garden experiment at two temperatures (20°C and 24°C) with genotypes of 13 natural populations ordered along a well-defined urbanization gradient. We also assessed body size and haemoglobin concentration to identify underlying physiological drivers of responses in CTMAX . We found a higher CTMAX in animals isolated from urban compared to rural habitats and in animals reared at higher temperatures. We also observed substantial genetic variation in thermal tolerance within populations. Overall, smaller animals were more heat tolerant. While urban animals mature at smaller size, the effect of urbanization on thermal tolerance is only in part caused by reductions in body size. Although urban Daphnia contained higher concentrations of haemoglobin, this did not contribute to their higher CTMAX . Our results provide evidence of adaptive thermal evolution to urbanization in the water flea Daphnia. In addition, our results show both evolutionary potential and adaptive plasticity in rural as well as urban Daphnia populations, facilitating responses to warming. Given the important ecological role of Daphnia in ponds and lakes, these adaptive responses likely impact food web dynamics, top-down control of algae, water quality, and the socio-economic value of urban ponds.
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Affiliation(s)
- Kristien I Brans
- Laboratory of Aquatic Ecology, Evolution and Conservation, KU Leuven, Leuven, Belgium
| | - Mieke Jansen
- Laboratory of Aquatic Ecology, Evolution and Conservation, KU Leuven, Leuven, Belgium
| | - Joost Vanoverbeke
- Laboratory of Aquatic Ecology, Evolution and Conservation, KU Leuven, Leuven, Belgium
- Research Institute for Nature and Forest (INBO), Brussel, Belgium
| | - Nedim Tüzün
- Laboratory of Aquatic Ecology, Evolution and Conservation, KU Leuven, Leuven, Belgium
| | - Robby Stoks
- Laboratory of Aquatic Ecology, Evolution and Conservation, KU Leuven, Leuven, Belgium
| | - Luc De Meester
- Laboratory of Aquatic Ecology, Evolution and Conservation, KU Leuven, Leuven, Belgium
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17
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QTL mapping of a natural genetic polymorphism for long-term parasite persistence in Daphnia populations. Parasitology 2017; 144:1686-1694. [DOI: 10.1017/s0031182017001032] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
SUMMARYKnowing the determinants of the geographic ranges of parasites is important for understanding their evolutionary ecology, epidemiology and their potential to expand their range. Here we explore the determinants of geographic range in the peculiar case of a parasite species – the microsporidian Hamiltosporidium tvaerminnensis – that has a limited geographic distribution in a wide-spread host – Daphnia magna. We conducted a quantitative trait loci (QTLs) analysis with monoclonal F2D. magna populations originating from a cross between a susceptible northern European genotype and a resistant central European genotype. Contrary to our expectations, long-term persistence turned out to be a quantitative trait across the F2 offspring. Evidence for two QTLs, one epistatic interaction and for further minor QTL was found. This finding contrasts markedly with the previously described bimodal pattern for long-term parasite persistence in natural host genotypes across Europe and leaves open the question of how a quantitative genetic trait could determine the disjunct geographic distribution of the parasite across Europe.
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18
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Reisser CMO, Fasel D, Hürlimann E, Dukic M, Haag-Liautard C, Thuillier V, Galimov Y, Haag CR. Transition from Environmental to Partial Genetic Sex Determination in Daphnia through the Evolution of a Female-Determining Incipient W Chromosome. Mol Biol Evol 2017; 34:575-588. [PMID: 28007974 DOI: 10.1093/molbev/msw251] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Sex chromosomes can evolve during the evolution of genetic sex determination (GSD) from environmental sex determination (ESD). Despite theoretical attention, early mechanisms involved in the transition from ESD to GSD have yet to be studied in nature. No mixed ESD-GSD animal species have been reported, except for some species of Daphnia, small freshwater crustaceans in which sex is usually determined solely by the environment, but in which a dominant female sex-determining locus is present in some populations. This locus follows Mendelian single-locus inheritance, but has otherwise not been characterized genetically. We now show that the sex-determining genomic region maps to the same low-recombining peri-centromeric region of linkage group 3 (LG3) in three highly divergent populations of D. magna, and spans 3.6 Mb. Despite low levels of recombination, the associated region contains signs of historical recombination, suggesting a role for selection acting on several genes thereby maintaining linkage disequilibrium among the 36 associated SNPs. The region carries numerous genes involved in sex differentiation in other taxa, including transformer2 and sox9. Taken together, the region determining the genetic females shows characteristics of a sex-related supergene, suggesting that LG3 is potentially an incipient W chromosome despite the lack of significant additional restriction of recombination between Z and W. The occurrence of the female-determining locus in a pre-existing low recombining region illustrates one possible form of recombination suppression in sex chromosomes. D. magna is a promising model for studying the evolutionary transitions from ESD to GSD and early sex chromosome evolution.
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Affiliation(s)
- Céline M O Reisser
- Centre d'Ecologie Fonctionnelle et Evolutive CEFE UMR 5175, CNRS Université de Montpellier Université Paul-Valéry Montpellier EPHE, Montpellier, France.,Université de Fribourg, Ecology and Evolution, Fribourg, Switzerland.,IFREMER Centre du Pacifique, Taravao, Tahiti, Polynésie Française
| | - Dominique Fasel
- Université de Fribourg, Ecology and Evolution, Fribourg, Switzerland
| | - Evelin Hürlimann
- Université de Fribourg, Ecology and Evolution, Fribourg, Switzerland
| | - Marinela Dukic
- Universität Basel, Zoology Institute, Evolutionary Biology, Basel, Switzerland
| | | | | | - Yan Galimov
- Koltsov Institute of Developmental Biology, Russian Academy of Sciences, Moscow, Russia
| | - Christoph R Haag
- Centre d'Ecologie Fonctionnelle et Evolutive CEFE UMR 5175, CNRS Université de Montpellier Université Paul-Valéry Montpellier EPHE, Montpellier, France.,Université de Fribourg, Ecology and Evolution, Fribourg, Switzerland
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19
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Dukić M, Berner D, Roesti M, Haag CR, Ebert D. A high-density genetic map reveals variation in recombination rate across the genome of Daphnia magna. BMC Genet 2016; 17:137. [PMID: 27737627 PMCID: PMC5064971 DOI: 10.1186/s12863-016-0445-7] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Accepted: 10/04/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Recombination rate is an essential parameter for many genetic analyses. Recombination rates are highly variable across species, populations, individuals and different genomic regions. Due to the profound influence that recombination can have on intraspecific diversity and interspecific divergence, characterization of recombination rate variation emerges as a key resource for population genomic studies and emphasises the importance of high-density genetic maps as tools for studying genome biology. Here we present such a high-density genetic map for Daphnia magna, and analyse patterns of recombination rate across the genome. RESULTS A F2 intercross panel was genotyped by Restriction-site Associated DNA sequencing to construct the third-generation linkage map of D. magna. The resulting high-density map included 4037 markers covering 813 scaffolds and contigs that sum up to 77 % of the currently available genome draft sequence (v2.4) and 55 % of the estimated genome size (238 Mb). Total genetic length of the map presented here is 1614.5 cM and the genome-wide recombination rate is estimated to 6.78 cM/Mb. Merging genetic and physical information we consistently found that recombination rate estimates are high towards the peripheral parts of the chromosomes, while chromosome centres, harbouring centromeres in D. magna, show very low recombination rate estimates. CONCLUSIONS Due to its high-density, the third-generation linkage map for D. magna can be coupled with the draft genome assembly, providing an essential tool for genome investigation in this model organism. Thus, our linkage map can be used for the on-going improvements of the genome assembly, but more importantly, it has enabled us to characterize variation in recombination rate across the genome of D. magna for the first time. These new insights can provide a valuable assistance in future studies of the genome evolution, mapping of quantitative traits and population genetic studies.
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Affiliation(s)
- Marinela Dukić
- University of Basel, Zoological Institute, Vesalgasse 1, Basel, CH-4051, Switzerland.
| | - Daniel Berner
- University of Basel, Zoological Institute, Vesalgasse 1, Basel, CH-4051, Switzerland
| | - Marius Roesti
- University of Basel, Zoological Institute, Vesalgasse 1, Basel, CH-4051, Switzerland.,Biodiversity Research Centre and Zoology Department, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | - Christoph R Haag
- Centre d'Ecologie Fonctionnelle et Evolutive - CEFE UMR 5175, CNRS - Université de Montpellier - Université Paul-Valéry Montpellier - EPHE, campus CNRS, 1919, route de Mende, 34293, Montpellier Cedex 5, France.,Department of Biology, Ecology and Evolution, University of Fribourg, Chemin du Muśee 10, 1700, Fribourg, Switzerland
| | - Dieter Ebert
- University of Basel, Zoological Institute, Vesalgasse 1, Basel, CH-4051, Switzerland
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20
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Roulin AC, Bourgeois Y, Stiefel U, Walser JC, Ebert D. A Photoreceptor Contributes to the Natural Variation of Diapause Induction inDaphnia magna. Mol Biol Evol 2016; 33:3194-3204. [DOI: 10.1093/molbev/msw200] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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21
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Arbore R, Andras JP, Routtu J, Ebert D. Ecological genetics of sediment browsing behaviour in a planktonic crustacean. J Evol Biol 2016; 29:1999-2009. [PMID: 27329766 DOI: 10.1111/jeb.12923] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Revised: 05/30/2016] [Accepted: 06/15/2016] [Indexed: 02/03/2023]
Abstract
Zooplankton can display complex habitat selection behaviours that influence the way they interact with their environments. Some species, although primarily pelagic, can exploit sediment-borne particles as a food source or use sediments as a refuge from pelagic predation. However, this strategy may increase the exposure to other risks such as benthic predation and infection from sediment-borne parasite transmission stages. The evolution of habitat selection behaviour in these species is thus expected to be influenced by multiple and possibly contrasting selective forces. Here, we study the browsing behaviour of the water flea Daphnia magna on bottom sediments. First, we demonstrated genetic variation for sediment browsing among D. magna genotypes from natural populations sampled across a broad geographic range. Next, we used an F2 recombinant panel to perform a QTL analysis and identified three regions in the D. magna genome contributing to variation in browsing behaviour. We also analysed the correlation between our data and previously published data on the phototactic behaviour of genotypes from the same F2 panel. Clonal means of the two behavioral traits were not correlated, suggesting that they may evolve independently. Browsing behaviour is likely to be a relevant component of habitat selection in D. magna, and its study may help to incorporate the interactions with the sediment into eco-evolutionary models of this key freshwater species.
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Affiliation(s)
- R Arbore
- Department of Environmental Sciences, Zoological Institute, University of Basel, Basel, Switzerland.
| | - J P Andras
- Department of Environmental Sciences, Zoological Institute, University of Basel, Basel, Switzerland.,Department of Biological Sciences, Mount Holyoke College, South Hadley, MA, USA
| | - J Routtu
- Department of Environmental Sciences, Zoological Institute, University of Basel, Basel, Switzerland.,Department of Molecular Ecology, Institute of Biology, Martin-Luther-Universität Halle-Wittenberg, Halle (Saale), Germany
| | - D Ebert
- Department of Environmental Sciences, Zoological Institute, University of Basel, Basel, Switzerland
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22
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Daphnia magna transcriptome by RNA-Seq across 12 environmental stressors. Sci Data 2016; 3:160030. [PMID: 27164179 PMCID: PMC4862326 DOI: 10.1038/sdata.2016.30] [Citation(s) in RCA: 71] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Accepted: 04/19/2016] [Indexed: 11/08/2022] Open
Abstract
The full exploration of gene-environment interactions requires model organisms with well-characterized ecological interactions in their natural environment, manipulability in the laboratory and genomic tools. The waterflea Daphnia magna is an established ecological and toxicological model species, central to the food webs of freshwater lentic habitats and sentinel for water quality. Its tractability and cyclic parthenogenetic life-cycle are ideal to investigate links between genes and the environment. Capitalizing on this unique model system, the STRESSFLEA consortium generated a comprehensive RNA-Seq data set by exposing two inbred genotypes of D. magna and a recombinant cross of these genotypes to a range of environmental perturbations. Gene models were constructed from the transcriptome data and mapped onto the draft genome of D. magna using EvidentialGene. The transcriptome data generated here, together with the available draft genome sequence of D. magna and a high-density genetic map will be a key asset for future investigations in environmental genomics.
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23
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Metzger CMJA, Luijckx P, Bento G, Mariadassou M, Ebert D. The Red Queen lives: Epistasis between linked resistance loci. Evolution 2016; 70:480-7. [DOI: 10.1111/evo.12854] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2015] [Revised: 01/04/2016] [Accepted: 01/05/2016] [Indexed: 02/05/2023]
Affiliation(s)
| | - Pepijn Luijckx
- Zoological Institute; University of Basel; CH-4051 Basel Switzerland
- Department of Ecology & Evolutionary Biology; University of Toronto; M5S 3B2 Toronto Ontario Canada
| | - Gilberto Bento
- Zoological Institute; University of Basel; CH-4051 Basel Switzerland
| | - Mahendra Mariadassou
- Zoological Institute; University of Basel; CH-4051 Basel Switzerland
- INRA, UR1404 Unité Mathématique et Informatique Appliquées du Génome à l'Environnement; 78350 Jouy-en-Josas France
| | - Dieter Ebert
- Zoological Institute; University of Basel; CH-4051 Basel Switzerland
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24
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Toyota K, Hiruta C, Ogino Y, Miyagawa S, Okamura T, Onishi Y, Tatarazako N, Iguchi T. Comparative Developmental Staging of Female and Male Water Fleas Daphnia pulex and Daphnia magna During Embryogenesis. Zoolog Sci 2016; 33:31-7. [DOI: 10.2108/zs150116] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Affiliation(s)
- Kenji Toyota
- Okazaki Institute for Integrative Bioscience, National Institute for Basic Biology, National Institutes of Natural Sciences, and Department of Basic Biology, Faculty of Life Science, SOKENDAI (Graduate University for Advanced Studies), 5-1 Higashiyam
| | - Chizue Hiruta
- Okazaki Institute for Integrative Bioscience, National Institute for Basic Biology, National Institutes of Natural Sciences, and Department of Basic Biology, Faculty of Life Science, SOKENDAI (Graduate University for Advanced Studies), 5-1 Higashiyam
| | - Yukiko Ogino
- Okazaki Institute for Integrative Bioscience, National Institute for Basic Biology, National Institutes of Natural Sciences, and Department of Basic Biology, Faculty of Life Science, SOKENDAI (Graduate University for Advanced Studies), 5-1 Higashiyam
| | - Shinichi Miyagawa
- Okazaki Institute for Integrative Bioscience, National Institute for Basic Biology, National Institutes of Natural Sciences, and Department of Basic Biology, Faculty of Life Science, SOKENDAI (Graduate University for Advanced Studies), 5-1 Higashiyam
| | - Tetsuro Okamura
- Institute of Environmental Ecology, IDEA Consultants, Inc., 1334-5 Riemon, Yaizu, Shizuoka 421-0212, Japan
| | - Yuta Onishi
- Institute of Environmental Ecology, IDEA Consultants, Inc., 1334-5 Riemon, Yaizu, Shizuoka 421-0212, Japan
| | - Norihisa Tatarazako
- Environmental Quality Measurement Section, Research Center for Environmental Risk, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506, Japan
| | - Taisen Iguchi
- Okazaki Institute for Integrative Bioscience, National Institute for Basic Biology, National Institutes of Natural Sciences, and Department of Basic Biology, Faculty of Life Science, SOKENDAI (Graduate University for Advanced Studies), 5-1 Higashiyam
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25
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Gómez R, Van Damme K, Gosálvez J, Morán ES, Colbourne JK. Male meiosis in Crustacea: synapsis, recombination, epigenetics and fertility in Daphnia magna. Chromosoma 2015; 125:769-87. [PMID: 26685998 PMCID: PMC5023733 DOI: 10.1007/s00412-015-0558-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Revised: 10/28/2015] [Accepted: 11/09/2015] [Indexed: 11/28/2022]
Abstract
We present the first detailed cytological study of male meiosis in Daphnia (Crustacea: Branchiopoda: Cladocera)—an aquatic microcrustacean with a cyclical parthenogenetic life cycle. Using immunostaining of the testes in Daphnia magna for baseline knowledge, we characterized the different stages of meiotic division and spermiogenesis in relation to the distribution of proteins involved in synapsis, early recombination events and sister chromatid cohesion. We also studied post-translational histone modifications in male spermatocytes, in relation to the dynamic chromatin progression of meiosis. Finally, we applied a DNA fragmentation test to measure sperm quality of D. magna, with respect to levels of inbreeding. As a proxy for fertility, this technique may be used to assess the reproductive health of a sentinel species of aquatic ecosystems. Daphnia proves to be a model species for comparative studies of meiosis that is poised to improve our understanding of the cytological basis of sexual and asexual reproduction.
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Affiliation(s)
- Rocío Gómez
- Departamento de Biología, Facultad de Ciencias, Universidad Autónoma de Madrid, E-28049, Madrid, Spain. .,Environmental Genomics Group. School of Biosciences, University of Birmingham, Edgbaston, B15 2TT, UK. .,Chromosome Dynamics Group. School of Biosciences, University of Birmingham, Edgbaston, B15 2TT, UK.
| | - Kay Van Damme
- Environmental Genomics Group. School of Biosciences, University of Birmingham, Edgbaston, B15 2TT, UK
| | - Jaime Gosálvez
- Departamento de Biología, Facultad de Ciencias, Universidad Autónoma de Madrid, E-28049, Madrid, Spain
| | - Eugenio Sánchez Morán
- Chromosome Dynamics Group. School of Biosciences, University of Birmingham, Edgbaston, B15 2TT, UK
| | - John K Colbourne
- Environmental Genomics Group. School of Biosciences, University of Birmingham, Edgbaston, B15 2TT, UK
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26
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Ebert D, Duneau D, Hall MD, Luijckx P, Andras JP, Du Pasquier L, Ben-Ami F. A Population Biology Perspective on the Stepwise Infection Process of the Bacterial Pathogen Pasteuria ramosa in Daphnia. ADVANCES IN PARASITOLOGY 2015; 91:265-310. [PMID: 27015951 DOI: 10.1016/bs.apar.2015.10.001] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The infection process of many diseases can be divided into series of steps, each one required to successfully complete the parasite's life and transmission cycle. This approach often reveals that the complex phenomenon of infection is composed of a series of more simple mechanisms. Here we demonstrate that a population biology approach, which takes into consideration the natural genetic and environmental variation at each step, can greatly aid our understanding of the evolutionary processes shaping disease traits. We focus in this review on the biology of the bacterial parasite Pasteuria ramosa and its aquatic crustacean host Daphnia, a model system for the evolutionary ecology of infectious disease. Our analysis reveals tremendous differences in the degree to which the environment, host genetics, parasite genetics and their interactions contribute to the expression of disease traits at each of seven different steps. This allows us to predict which steps may respond most readily to selection and which steps are evolutionarily constrained by an absence of variation. We show that the ability of Pasteuria to attach to the host's cuticle (attachment step) stands out as being strongly influenced by the interaction of host and parasite genotypes, but not by environmental factors, making it the prime candidate for coevolutionary interactions. Furthermore, the stepwise approach helps us understanding the evolution of resistance, virulence and host ranges. The population biological approach introduced here is a versatile tool that can be easily transferred to other systems of infectious disease.
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Affiliation(s)
- Dieter Ebert
- Zoological Institute, University of Basel, Basel, Switzerland
| | - David Duneau
- Zoological Institute, University of Basel, Basel, Switzerland; Department Ecologie et Diversité Biologique, University Paul Sabatier-Toulouse III, Toulouse, France
| | - Matthew D Hall
- Zoological Institute, University of Basel, Basel, Switzerland; Monash University, School of Biological Sciences, Clayton Campus, Melbourne, VIC, Australia
| | - Pepijn Luijckx
- Zoological Institute, University of Basel, Basel, Switzerland; Department of Ecology & Evolutionary Biology, University of Toronto, Toronto, ON, Canada
| | - Jason P Andras
- Zoological Institute, University of Basel, Basel, Switzerland; Department of Biological Sciences, Mount Holyoke College, South Hadley, MA, USA
| | | | - Frida Ben-Ami
- Department of Zoology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
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Svendsen N, Reisser CMO, Dukić M, Thuillier V, Ségard A, Liautard-Haag C, Fasel D, Hürlimann E, Lenormand T, Galimov Y, Haag CR. Uncovering Cryptic Asexuality in Daphnia magna by RAD Sequencing. Genetics 2015; 201:1143-55. [PMID: 26341660 PMCID: PMC4649641 DOI: 10.1534/genetics.115.179879] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Accepted: 08/29/2015] [Indexed: 02/06/2023] Open
Abstract
The breeding systems of many organisms are cryptic and difficult to investigate with observational data, yet they have profound effects on a species' ecology, evolution, and genome organization. Genomic approaches offer a novel, indirect way to investigate breeding systems, specifically by studying the transmission of genetic information from parents to offspring. Here we exemplify this method through an assessment of self-fertilization vs. automictic parthenogenesis in Daphnia magna. Self-fertilization reduces heterozygosity by 50% compared to the parents, but under automixis, whereby two haploid products from a single meiosis fuse, the expected heterozygosity reduction depends on whether the two meiotic products are separated during meiosis I or II (i.e., central vs. terminal fusion). Reviewing the existing literature and incorporating recombination interference, we derive an interchromosomal and an intrachromosomal prediction of how to distinguish various forms of automixis from self-fertilization using offspring heterozygosity data. We then test these predictions using RAD-sequencing data on presumed automictic diapause offspring of so-called nonmale producing strains and compare them with "self-fertilized" offspring produced by within-clone mating. The results unequivocally show that these offspring were produced by automixis, mostly, but not exclusively, through terminal fusion. However, the results also show that this conclusion was only possible owing to genome-wide heterozygosity data, with phenotypic data as well as data from microsatellite markers yielding inconclusive or even misleading results. Our study thus demonstrates how to use the power of genomic approaches for elucidating breeding systems, and it provides the first demonstration of automictic parthenogenesis in Daphnia.
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Affiliation(s)
- Nils Svendsen
- Centre d'Ecologie Fonctionnelle et Evolutive (CEFE)-Unité Mixte de Recherche 5175, Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier-Université Paul-Valéry Montpellier-Ecole Pratique des Hautes Etudes (EPHE), campus CNRS, 19, 34293 Montpellier Cedex 5, France
| | - Celine M O Reisser
- Centre d'Ecologie Fonctionnelle et Evolutive (CEFE)-Unité Mixte de Recherche 5175, Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier-Université Paul-Valéry Montpellier-Ecole Pratique des Hautes Etudes (EPHE), campus CNRS, 19, 34293 Montpellier Cedex 5, France Ecology and Evolution, University of Fribourg, 1700 Fribourg, Switzerland
| | - Marinela Dukić
- Zoology Institute, Evolutionary Biology, University of Basel, 4051 Basel, Switzerland
| | - Virginie Thuillier
- Ecology and Evolution, University of Fribourg, 1700 Fribourg, Switzerland
| | - Adeline Ségard
- Centre d'Ecologie Fonctionnelle et Evolutive (CEFE)-Unité Mixte de Recherche 5175, Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier-Université Paul-Valéry Montpellier-Ecole Pratique des Hautes Etudes (EPHE), campus CNRS, 19, 34293 Montpellier Cedex 5, France
| | | | - Dominique Fasel
- Ecology and Evolution, University of Fribourg, 1700 Fribourg, Switzerland
| | - Evelin Hürlimann
- Ecology and Evolution, University of Fribourg, 1700 Fribourg, Switzerland
| | - Thomas Lenormand
- Centre d'Ecologie Fonctionnelle et Evolutive (CEFE)-Unité Mixte de Recherche 5175, Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier-Université Paul-Valéry Montpellier-Ecole Pratique des Hautes Etudes (EPHE), campus CNRS, 19, 34293 Montpellier Cedex 5, France
| | - Yan Galimov
- Koltsov Institute of Developmental Biology, Russian Academy of Sciences, 119334 Moscow, Russia
| | - Christoph R Haag
- Centre d'Ecologie Fonctionnelle et Evolutive (CEFE)-Unité Mixte de Recherche 5175, Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier-Université Paul-Valéry Montpellier-Ecole Pratique des Hautes Etudes (EPHE), campus CNRS, 19, 34293 Montpellier Cedex 5, France Ecology and Evolution, University of Fribourg, 1700 Fribourg, Switzerland
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Fields PD, Reisser C, Dukić M, Haag CR, Ebert D. Genes mirror geography inDaphnia magna. Mol Ecol 2015; 24:4521-36. [DOI: 10.1111/mec.13324] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2015] [Revised: 07/13/2015] [Accepted: 07/14/2015] [Indexed: 02/06/2023]
Affiliation(s)
- Peter D. Fields
- Zoological Institute; University of Basel; Vesalgasse 1 Basel CH-4051 Switzerland
| | - Céline Reisser
- Centre d'Ecologie Fonctionnelle et Evolutive - UMR 5175; campus CNRS 1919 route de Mende 34293 Montpellier Cedex 5 France
- Department of Biology; Ecology and Evolution; University of Fribourg; Chemin du Muśee 10 1700 Fribourg Switzerland
| | - Marinela Dukić
- Zoological Institute; University of Basel; Vesalgasse 1 Basel CH-4051 Switzerland
| | - Christoph R. Haag
- Centre d'Ecologie Fonctionnelle et Evolutive - UMR 5175; campus CNRS 1919 route de Mende 34293 Montpellier Cedex 5 France
- Department of Biology; Ecology and Evolution; University of Fribourg; Chemin du Muśee 10 1700 Fribourg Switzerland
| | - Dieter Ebert
- Zoological Institute; University of Basel; Vesalgasse 1 Basel CH-4051 Switzerland
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LeBlanc GA, Medlock EK. Males on demand: the environmental-neuro-endocrine control of male sex determination in daphnids. FEBS J 2015; 282:4080-93. [DOI: 10.1111/febs.13393] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Revised: 07/27/2015] [Accepted: 07/30/2015] [Indexed: 11/28/2022]
Affiliation(s)
- Gerald A. LeBlanc
- Department of Biological Sciences; North Carolina State University; Raleigh NC USA
| | - Elizabeth K. Medlock
- Department of Biological Sciences; North Carolina State University; Raleigh NC USA
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An SNP-based second-generation genetic map of Daphnia magna and its application to QTL analysis of phenotypic traits. BMC Genomics 2014; 15:1033. [PMID: 25431334 PMCID: PMC4301878 DOI: 10.1186/1471-2164-15-1033] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2014] [Accepted: 11/12/2014] [Indexed: 02/08/2023] Open
Abstract
Background Although Daphnia is increasingly recognized as a model for ecological genomics and biomedical research, there is, as of yet, no high-resolution genetic map for the genus. Such a map would provide an important tool for mapping phenotypes and assembling the genome. Here we estimate the genome size of Daphnia magna and describe the construction of an SNP array based linkage map. We then test the suitability of the map for life history and behavioural trait mapping. The two parent genotypes used to produce the map derived from D. magna populations with and without fish predation, respectively and are therefore expected to show divergent behaviour and life-histories. Results Using flow cytometry we estimated the genome size of D. magna to be about 238 mb. We developed an SNP array tailored to type SNPs in a D. magna F2 panel and used it to construct a D. magna linkage map, which included 1,324 informative markers. The map produced ten linkage groups ranging from 108.9 to 203.6 cM, with an average distance between markers of 1.13 cM and a total map length of 1,483.6 cM (Kosambi corrected). The physical length per cM is estimated to be 160 kb. Mapping infertility genes, life history traits and behavioural traits on this map revealed several significant QTL peaks and showed a complex pattern of underlying genetics, with different traits showing strongly different genetic architectures. Conclusions The new linkage map of D. magna constructed here allowed us to characterize genetic differences among parent genotypes from populations with ecological differences. The QTL effect plots are partially consistent with our expectation of local adaptation under contrasting predation regimes. Furthermore, the new genetic map will be an important tool for the Daphnia research community and will contribute to the physical map of the D. magna genome project and the further mapping of phenotypic traits. The clones used to produce the linkage map are maintained in a stock collection and can be used for mapping QTLs of traits that show variance among the F2 clones. Electronic supplementary material The online version of this article (doi:10.1186/1471-2164-15-1033) contains supplementary material, which is available to authorized users.
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31
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Routtu J, Ebert D. Genetic architecture of resistance in Daphnia hosts against two species of host-specific parasites. Heredity (Edinb) 2014; 114:241-8. [PMID: 25335558 DOI: 10.1038/hdy.2014.97] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2014] [Revised: 08/21/2014] [Accepted: 08/27/2014] [Indexed: 02/04/2023] Open
Abstract
Understanding the genetic architecture of host resistance is key for understanding the evolution of host-parasite interactions. Evolutionary models often assume simple genetics based on few loci and strong epistasis. It is unknown, however, whether these assumptions apply to natural populations. Using a quantitative trait loci (QTL) approach, we explore the genetic architecture of resistance in the crustacean Daphnia magna to two of its natural parasites: the horizontally transmitted bacterium Pasteuria ramosa and the horizontally and vertically transmitted microsporidium Hamiltosporidium tvaerminnensis. These two systems have become models for studies on the evolution of host-parasite interactions. In the QTL panel used here, Daphnia's resistance to P. ramosa is controlled by a single major QTL (which explains 50% of the observed variation). Resistance to H. tvaerminnensis horizontal infections shows a signature of a quantitative trait based in multiple loci with weak epistatic interactions (together explaining 38% variation). Resistance to H. tvaerminnensis vertical infections, however, shows only one QTL (explaining 13.5% variance) that colocalizes with one of the QTLs for horizontal infections. QTLs for resistance to Pasteuria and Hamiltosporidium do not colocalize. We conclude that the genetics of resistance in D. magna are drastically different for these two parasites. Furthermore, we infer that based on these and earlier results, the mechanisms of coevolution differ strongly for the two host-parasite systems. Only the Pasteuria-Daphnia system is expected to follow the negative frequency-dependent selection (Red Queen) model. How coevolution works in the Hamiltosporidium-Daphnia system remains unclear.
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Affiliation(s)
- J Routtu
- Zoologisches Institut, Universität Basel, Basel, Switzerland
| | - D Ebert
- Zoologisches Institut, Universität Basel, Basel, Switzerland
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Hochmuth JD, Asselman J, De Schamphelaere KAC. Are interactive effects of harmful algal blooms and copper pollution a concern for water quality management? WATER RESEARCH 2014; 60:41-53. [PMID: 24821194 DOI: 10.1016/j.watres.2014.03.041] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2013] [Revised: 02/07/2014] [Accepted: 03/17/2014] [Indexed: 06/03/2023]
Abstract
Toxicity of mixtures of stressors is one of the major challenges in water quality management. Yet until now risk assessment focuses almost exclusively on the effect characterization of individual stressors. An important concern is the potential interactive effects of cyanobacteria, sometimes referred to as harmful algal blooms, with chemical stressors. Here, we evaluated the response of two clones of the freshwater cladoceran Daphnia magna to the combined effects of five cyanobacteria and copper. The latter remains the most commonly applied chemical algaecide and is also often detected in eutrophic run-offs that promote harmful algal blooms. Because the different cyanobacteria studied here have known modes of action that are similar, as well as dissimilar compared to the known modes of actions of copper, we based our assessment on two widely used reference models, i.e. the Concentration Addition (CA) model for similarly acting stressors and the Independent Action (IA) model for dissimilarly acting stressors. We highlight four major findings. First, the conclusions drawn on the interaction type (non-interaction vs. synergism or antagonism) between either of the five cyanobacteria species and copper were the same for both D. magna clones. Second, the interaction type differed between the Microcystis + copper mixture (non-interaction according to CA and synergism according to IA) and the four other cyanobacteria + copper mixtures (antagonism according to CA and non-interaction according to IA). Third, both reference models provided reasonable predictions for all observed mixture toxicities. Fourth, we consistently obtained different results with the IA reference model compared to the CA model. More specifically, mixtures of Cu and Microcystis were synergistic with IA whereas non-interaction was observed with CA, while the remaining four cyanobacteria + copper combinations all displayed non-interaction with IA and antagonism with CA. Despite the IA reference model providing a marginally better fit to the data in general, the CA reference model delivered more conservative predictions for mixture toxicity of cyanobacteria + copper in all cases compared to the IA reference model. Thus, the CA model could serve as a conservative model to account for mixture toxicity of cyanobacteria and copper in water quality management, as it gives rise to conservative predictions of mixed stressor toxicity at sub-lethal effect levels in D. magna. Finally, and in accordance with other studies of cyanobacteria + chemical mixtures, we did not detect any strong synergistic effects of copper and cyanobacteria mixtures on D. magna. Consequently, based on our study with the model freshwater zooplankton species Daphnia, interactive effects of harmful algal blooms and copper pollution appear to be of limited concern for water quality management.
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Affiliation(s)
- Jennifer D Hochmuth
- Laboratory of Environmental Toxicology and Aquatic Ecology, Environmental Toxicology Unit, Ghent University, J. Plateaustraat 22, B-9000 Ghent, Belgium.
| | - Jana Asselman
- Laboratory of Environmental Toxicology and Aquatic Ecology, Environmental Toxicology Unit, Ghent University, J. Plateaustraat 22, B-9000 Ghent, Belgium
| | - Karel A C De Schamphelaere
- Laboratory of Environmental Toxicology and Aquatic Ecology, Environmental Toxicology Unit, Ghent University, J. Plateaustraat 22, B-9000 Ghent, Belgium
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Water fleas require microbiota for survival, growth and reproduction. ISME JOURNAL 2014; 9:59-67. [PMID: 25026374 DOI: 10.1038/ismej.2014.116] [Citation(s) in RCA: 87] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2013] [Revised: 05/27/2014] [Accepted: 06/07/2014] [Indexed: 02/07/2023]
Abstract
Microbiota have diverse roles in the functioning of their hosts; experiments using model organisms have enabled investigations into these functions. In the model crustacean Daphnia, little knowledge exists about the effect of microbiota on host well being. We assessed the effect of microbiota on Daphnia magna by experimentally depriving animals of their microbiota and comparing their growth, survival and fecundity to that of their bacteria-bearing counterparts. We tested Daphnia coming from both lab-reared parthenogenetic eggs of a single genotype and from genetically diverse field-collected resting eggs. We showed that bacteria-free hosts are smaller, less fecund and have higher mortality than those with microbiota. We also manipulated the association by exposing bacteria-free Daphnia to a single bacterial strain of Aeromonas sp., and to laboratory environmental bacteria. These experiments further demonstrated that the Daphnia-microbiota system is amenable to manipulation under various experimental conditions. The results of this study have implications for studies of D. magna in ecotoxicology, ecology and environmental genomics.
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Roulin AC, Routtu J, Hall MD, Janicke T, Colson I, Haag CR, Ebert D. Local adaptation of sex induction in a facultative sexual crustacean: insights from QTL mapping and natural populations of Daphnia magna. Mol Ecol 2013; 22:3567-79. [PMID: 23786714 DOI: 10.1111/mec.12308] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2012] [Revised: 02/12/2013] [Accepted: 02/17/2013] [Indexed: 02/02/2023]
Abstract
Dormancy is a common adaptation in invertebrates to survive harsh conditions. Triggered by environmental cues, populations produce resting eggs that allow them to survive temporally unsuitable conditions. Daphnia magna is a crustacean that reproduces by cyclical parthenogenesis, alternating between the production of asexual offspring and the sexual reproduction of diapausing eggs (ephippia). Prior to ephippia production, males (necessary to ensure ephippia fertilization) are produced parthenogenetically. Both the production of ephippia and the parthenogenetic production of males are induced by environmental factors. Here, we test the hypothesis that the induction of D. magna resting egg production shows a signature of local adaptation. We postulated that Daphnia from permanent ponds would produce fewer ephippia and males than Daphnia from intermittent ponds and that the frequency and season of habitat deterioration would correlate with the timing and amount of male and ephippia production. To test this, we quantified the production of males and ephippia in clonal D. magna populations in several different controlled environments. We found that the production of both ephippia and males varies strongly among populations in a way that suggests local adaptation. By performing quantitative trait locus mapping with parent clones from contrasting pond environments, we identified nonoverlapping genomic regions associated with male and ephippia production. As the traits are influenced by two different genomic regions, and both are necessary for successful resting egg production, we suggest that the genes for their induction co-evolve.
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Affiliation(s)
- Anne C Roulin
- Department of Evolutionary Biology, Zoological Institute, University of Basel, Vesalgasse 1, Basel, Switzerland.
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De Vos S, Bossier P, Van Stappen G, Vercauteren I, Sorgeloos P, Vuylsteke M. A first AFLP-based genetic linkage map for brine shrimp Artemia franciscana and its application in mapping the sex locus. PLoS One 2013; 8:e57585. [PMID: 23469207 PMCID: PMC3587612 DOI: 10.1371/journal.pone.0057585] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2012] [Accepted: 01/22/2013] [Indexed: 12/26/2022] Open
Abstract
We report on the construction of sex-specific linkage maps, the identification of sex-linked markers and the genome size estimation for the brine shrimp Artemia franciscana. Overall, from the analysis of 433 AFLP markers segregating in a 112 full-sib family we identified 21 male and 22 female linkage groups (2n = 42), covering 1,041 and 1,313 cM respectively. Fifteen putatively homologous linkage groups, including the sex linkage groups, were identified between the female and male linkage map. Eight sex-linked AFLP marker alleles were inherited from the female parent, supporting the hypothesis of a WZ-ZZ sex-determining system. The haploid Artemia genome size was estimated to 0.93 Gb by flow cytometry. The produced Artemia linkage maps provide the basis for further fine mapping and exploring of the sex-determining region and are a possible marker resource for mapping genomic loci underlying phenotypic differences among Artemia species.
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Affiliation(s)
- Stephanie De Vos
- Laboratory of Aquaculture, Artemia Reference Center (ARC), Department of Animal Production, Ghent University, Gent, Belgium
- Department of Plant Systems Biology, VIB, Gent, Belgium
- Department of Biotechnology and Bioinformatics, Ghent University, Gent, Belgium
| | - Peter Bossier
- Laboratory of Aquaculture, Artemia Reference Center (ARC), Department of Animal Production, Ghent University, Gent, Belgium
| | - Gilbert Van Stappen
- Laboratory of Aquaculture, Artemia Reference Center (ARC), Department of Animal Production, Ghent University, Gent, Belgium
| | - Ilse Vercauteren
- Department of Plant Systems Biology, VIB, Gent, Belgium
- Department of Biotechnology and Bioinformatics, Ghent University, Gent, Belgium
| | - Patrick Sorgeloos
- Laboratory of Aquaculture, Artemia Reference Center (ARC), Department of Animal Production, Ghent University, Gent, Belgium
| | - Marnik Vuylsteke
- Department of Plant Systems Biology, VIB, Gent, Belgium
- Department of Biotechnology and Bioinformatics, Ghent University, Gent, Belgium
- * E-mail:
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Kakioka R, Kokita T, Kumada H, Watanabe K, Okuda N. A RAD-based linkage map and comparative genomics in the gudgeons (genus Gnathopogon, Cyprinidae). BMC Genomics 2013; 14:32. [PMID: 23324215 PMCID: PMC3583795 DOI: 10.1186/1471-2164-14-32] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2012] [Accepted: 01/14/2013] [Indexed: 11/10/2022] Open
Abstract
Background The construction of linkage maps is a first step in exploring the genetic basis for adaptive phenotypic divergence in closely related species by quantitative trait locus (QTL) analysis. Linkage maps are also useful for comparative genomics in non-model organisms. Advances in genomics technologies make it more feasible than ever to study the genetics of adaptation in natural populations. Restriction-site associated DNA (RAD) sequencing in next-generation sequencers facilitates the development of many genetic markers and genotyping. We aimed to construct a linkage map of the gudgeons of the genus Gnathopogon (Cyprinidae) for comparative genomics with the zebrafish Danio rerio (a member of the same family as gudgeons) and for the future QTL analysis of the genetic architecture underlying adaptive phenotypic evolution of Gnathopogon. Results We constructed the first genetic linkage map of Gnathopogon using a 198 F2 interspecific cross between two closely related species in Japan: river-dwelling Gnathopogon elongatus and lake-dwelling Gnathopogon caerulescens. Based on 1,622 RAD-tag markers, a linkage map spanning 1,390.9 cM with 25 linkage groups and an average marker interval of 0.87 cM was constructed. We also identified a region involving female-specific transmission ratio distortion (TRD). Synteny and collinearity were extensively conserved between Gnathopogon and zebrafish. Conclusions The dense SNP-based linkage map presented here provides a basis for future QTL analysis. It will also be useful for transferring genomic information from a “traditional” model fish species, zebrafish, to screen candidate genes underlying ecologically important traits of the gudgeons.
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Affiliation(s)
- Ryo Kakioka
- Department of Zoology, Graduate School of Science, Kyoto University, Kitashirakawa-Oiwake-cho, Sakyo-ku, 606-8502, Kyoto, Japan.
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Orsini L, Mergeay J, Vanoverbeke J, De Meester L. The role of selection in driving landscape genomic structure of the waterflea Daphnia magna. Mol Ecol 2012; 22:583-601. [PMID: 23174029 DOI: 10.1111/mec.12117] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2012] [Revised: 10/08/2012] [Accepted: 10/11/2012] [Indexed: 01/08/2023]
Abstract
The combined analysis of neutral and adaptive genetic variation is crucial to reconstruct the processes driving population genetic structure in the wild. However, such combined analysis is challenging because of the complex interaction among neutral and selective processes in the landscape. Overcoming this level of complexity requires an unbiased search for the evidence of selection in the genomes of populations sampled from their natural habitats and the identification of demographic processes that lead to present-day populations' genetic structure. Ecological model species with a suite of genomic tools and well-understood ecologies are best suited to resolve this complexity and elucidate the role of selective and demographic processes in the landscape genomic structure of natural populations. Here we investigate the water flea Daphnia magna, an emerging model system in genomics and a renowned ecological model system. We infer past and recent demographic processes by contrasting patterns of local and regional neutral genetic diversity at markers with different mutation rates. We assess the role of the environment in driving genetic variation in our study system by identifying correlates between biotic and abiotic variables naturally occurring in the landscape and patterns of neutral and adaptive genetic variation. Our results indicate that selection plays a major role in determining the population genomic structure of D. magna. First, environmental selection directly impacts genetic variation at loci hitchhiking with genes under selection. Second, priority effects enhanced by local genetic adaptation (cf. monopolization) affect neutral genetic variation by reducing gene flow among populations and genetic diversity within populations.
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Affiliation(s)
- Luisa Orsini
- Laboratory of Aquatic Ecology, Evolution and Conservation, University of Leuven, Leuven, Belgium.
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The invasion history of the exotic freshwater zooplankter Daphnia lumholtzi (Cladocera, Crustacea) in North America: a genetic analysis. Biol Invasions 2012. [DOI: 10.1007/s10530-012-0329-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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ORSINI LUISA, SPANIER KATINAI, DE MEESTER LUC. Genomic signature of natural and anthropogenic stress in wild populations of the waterfleaDaphnia magna: validation in space, time and experimental evolution. Mol Ecol 2012; 21:2160-75. [DOI: 10.1111/j.1365-294x.2011.05429.x] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Resistance to a bacterial parasite in the crustacean Daphnia magna shows Mendelian segregation with dominance. Heredity (Edinb) 2011; 108:547-51. [PMID: 22167056 DOI: 10.1038/hdy.2011.122] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
The influence of host and parasite genetic background on infection outcome is a topic of great interest because of its pertinence to theoretical issues in evolutionary biology. In the present study, we use a classical genetics approach to examine the mode of inheritance of infection outcome in the crustacean Daphnia magna when exposed to the bacterial parasite Pasteuria ramosa. In contrast to previous studies in this system, we use a clone of P. ramosa, not field isolates, which allows for a more definitive interpretation of results. We test parental, F1, F2, backcross and selfed parental clones (total 284 genotypes) for susceptibility against a clone of P. ramosa using two different methods, infection trials and the recently developed attachment test. We find that D. magna clones reliably exhibit either complete resistance or complete susceptibility to P. ramosa clone C1 and that resistance is dominant, and inherited in a pattern consistent with Mendelian segregation of a single-locus with two alleles. The finding of a single host locus controlling susceptibility to P. ramosa suggests that the previously observed genotype-genotype interactions in this system have a simple genetic basis. This has important implications for the outcome of host-parasite co-evolution. Our results add to the growing body of evidence that resistance to parasites in invertebrates is mostly coded by one or few loci with dominance.
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Orsini L, Jansen M, Souche EL, Geldof S, De Meester L. Single nucleotide polymorphism discovery from expressed sequence tags in the waterflea Daphnia magna. BMC Genomics 2011; 12:309. [PMID: 21668940 PMCID: PMC3146954 DOI: 10.1186/1471-2164-12-309] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2010] [Accepted: 06/13/2011] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Daphnia (Crustacea: Cladocera) plays a central role in standing aquatic ecosystems, has a well known ecology and is widely used in population studies and environmental risk assessments. Daphnia magna is, especially in Europe, intensively used to study stress responses of natural populations to pollutants, climate change, and antagonistic interactions with predators and parasites, which have all been demonstrated to induce micro-evolutionary and adaptive responses. Although its ecology and evolutionary biology is intensively studied, little is known on the functional genomics underpinning of phenotypic responses to environmental stressors. The aim of the present study was to find genes expressed in presence of environmental stressors, and target such genes for single nucleotide polymorphic (SNP) marker development. RESULTS We developed three expressed sequence tag (EST) libraries using clonal lineages of D. magna exposed to ecological stressors, namely fish predation, parasite infection and pesticide exposure. We used these newly developed ESTs and other Daphnia ESTs retrieved from NCBI GeneBank to mine for SNP markers targeting synonymous as well as non synonymous genetic variation. We validate the developed SNPs in six natural populations of D. magna distributed at regional scale. CONCLUSIONS A large proportion (47%) of the produced ESTs are Daphnia lineage specific genes, which are potentially involved in responses to environmental stress rather than to general cellular functions and metabolic activities, or reflect the arthropod's aquatic lifestyle. The characterization of genes expressed under stress and the validation of their SNPs for population genetic study is important for identifying ecologically responsive genes in D. magna.
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Affiliation(s)
- Luisa Orsini
- Laboratory of Aquatic Ecology and Evolutionary Biology, K,U, Leuven, Ch, Deberiotstraat 32, 3000 Leuven, Belgium.
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Pritchard VL, Dimond L, Harrison JS, S Velázquez CC, Zieba JT, Burton RS, Edmands S. Interpopulation hybridization results in widespread viability selection across the genome in Tigriopus californicus. BMC Genet 2011; 12:54. [PMID: 21639918 PMCID: PMC3138442 DOI: 10.1186/1471-2156-12-54] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2010] [Accepted: 06/03/2011] [Indexed: 11/10/2022] Open
Abstract
Background Genetic interactions within hybrids influence their overall fitness. Understanding the details of these interactions can improve our understanding of speciation. One experimental approach is to investigate deviations from Mendelian expectations (segregation distortion) in the inheritance of mapped genetic markers. In this study, we used the copepod Tigriopus californicus, a species which exhibits high genetic divergence between populations and a general pattern of reduced fitness in F2 interpopulation hybrids. Previous studies have implicated both nuclear-cytoplasmic and nuclear-nuclear interactions in causing this fitness reduction. We identified and mapped population-diagnostic single nucleotide polymorphisms (SNPs) and used these to examine segregation distortion across the genome within F2 hybrids. Results We generated a linkage map which included 45 newly elucidated SNPs and 8 population-diagnostic microsatellites used in previous studies. The map, the first available for the Copepoda, was estimated to cover 75% of the genome and included markers on all 12 T. californicus chromosomes. We observed little segregation distortion in newly hatched F2 hybrid larvae (fewer than 10% of markers at p < 0.05), but strikingly higher distortion in F2 hybrid adult males (45% of markers at p < 0.05). Hence, segregation distortion was primarily caused by selection against particular genetic combinations which acted between hatching and maturity. Distorted markers were not distributed randomly across the genome but clustered on particular chromosomes. In contrast to other studies in this species we found little evidence for cytonuclear coadaptation. Instead, different linkage groups exhibited markedly different patterns of distortion, which appear to have been influenced by nuclear-nuclear epistatic interactions and may also reflect genetic load carried within the parental lines. Conclusion Adult male F2 hybrids between two populations of T. californius exhibit dramatic segregation distortion across the genome. Distorted loci are clustered within specific linkage groups, and the direction of distortion differs between chromosomes. This segregation distortion is due to selection acting between hatching and adulthood.
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Affiliation(s)
- Victoria L Pritchard
- Department of Biological Sciences, University of Southern California, Los Angeles, California 90089-0371, USA.
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Matthews B, Narwani A, Hausch S, Nonaka E, Peter H, Yamamichi M, Sullam KE, Bird KC, Thomas MK, Hanley TC, Turner CB. Toward an integration of evolutionary biology and ecosystem science. Ecol Lett 2011; 14:690-701. [PMID: 21554512 DOI: 10.1111/j.1461-0248.2011.01627.x] [Citation(s) in RCA: 203] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
At present, the disciplines of evolutionary biology and ecosystem science are weakly integrated. As a result, we have a poor understanding of how the ecological and evolutionary processes that create, maintain, and change biological diversity affect the flux of energy and materials in global biogeochemical cycles. The goal of this article was to review several research fields at the interfaces between ecosystem science, community ecology and evolutionary biology, and suggest new ways to integrate evolutionary biology and ecosystem science. In particular, we focus on how phenotypic evolution by natural selection can influence ecosystem functions by affecting processes at the environmental, population and community scale of ecosystem organization. We develop an eco-evolutionary model to illustrate linkages between evolutionary change (e.g. phenotypic evolution of producer), ecological interactions (e.g. consumer grazing) and ecosystem processes (e.g. nutrient cycling). We conclude by proposing experiments to test the ecosystem consequences of evolutionary changes.
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Affiliation(s)
- Blake Matthews
- EAWAG, Aquatic Ecology Department, Center for Ecology, Evolution and Biogeochemistry, Kastanienbaum 6047, Switzerland.
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Klerks PL, Xie L, Levinton JS. Quantitative genetics approaches to study evolutionary processes in ecotoxicology; a perspective from research on the evolution of resistance. ECOTOXICOLOGY (LONDON, ENGLAND) 2011; 20:513-23. [PMID: 21516382 DOI: 10.1007/s10646-011-0640-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 03/10/2011] [Indexed: 05/10/2023]
Abstract
Quantitative genetic approaches are often used to study evolutionary processes in ecotoxicology. This paper focuses on the evolution of resistance to environmental contaminants-an important evolutionary process in ecotoxicology. Three approaches are commonly employed to study the evolution of resistance: (1) Assessing whether a contaminant-exposed population has an increased resistance relative to a control population, using either spatial or temporal comparisons. (2) Estimating a population's heritability of resistance. (3) Investigating responses in a laboratory selection experiment. All three approaches provide valuable information on the potential for contaminants to affect a population's evolutionary trajectory via natural selection. However, all three approaches have inherent limitations, including difficulty in separating the various genetic and environmental variance components, responses being dependent on specific population and testing conditions, and inability to fully capture natural conditions in the laboratory. In order to maximize insights into the long-term consequences of adaptation, it is important to not just look at resistance itself, but also at the fitness consequences and at correlated responses in characteristics other than resistance. The rapid development of molecular genetics has yielded alternatives to the "black box" approach of quantitative genetics, but the presence of different limitations and strengths in the two fields means that they should be viewed as complementary rather than exchangeable. Quantitative genetics is benefiting from the incorporation of molecular tools and remains an important field for studying evolutionary toxicology.
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Affiliation(s)
- Paul L Klerks
- Department of Biology, University of Louisiana at Lafayette, Lafayette, LA 70504, USA.
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Abstract
Sequence analysis of the Daphnia pulex genome holds some surprises that could not have been anticipated from what was learned so far from other arthropod genomes. It establishes Daphnia as an eco-genetical model organism par excellence.
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